Drill and method of making the same



March 4 1924.

' 1,485,444 H. W. TWOGOOD DRILL AND METHOD OF MAKING THE SAME Filed Feb; 11. 1921 1 Patented Mar. 4, 1924.

- UNITED STATES Y W. TWOGOOD, OF nmorr, MICHIGAN, ASSIGNOB TO WHEEL TRUEING TOOL FFHE.

(.70., OF DETROIT, MICHIGAN.

DRILL AND METHOD OF :2.

me "ran-s;

This invention relate to drills, bits, and

borin tools that may be advantageously used %or drilling holes and recesses in concrete, brick and walls of 'indurate material,

for instance, to facilitate electrical workers in the mounting of brackets, insulators and hangers, and in extending wires or conduits in a building.

My invention aims to furnish a tool bodywith diamonds which will provide end and side cutting ed es, and the tool body is.

shaped to aflor clearance for material removed by the diamonds. Y

My invention involves a method of mounting the diamonds so that the same are ositively anchored against accidental disp acement during the operation of a drill, and in carryin my method into efiect, I may utilize a fluted or spirally grooved tool body, al-. so ready an article of commerce, or I may provide a special tool body as a new article of manufacture. In either instance, the outer end of the body is provided with diamonds, one of which serves as a centering medium as for starting and maintaining the tool body in a desired position while the other diamonds ream out or bore a hole, it' being understood that the tool may be driven by an electric motor or from a suitable source of ac power.

The construction entering into my tool and the method of producin the same will be hereinafter described an then claimed, and reference will now be had to the draw as in wherein- Figure 1 is a side elevation of a longitudinally fluted tool body or reamer, in which diamonds have been mounted in accordance' with my invention; I

Fig. 2 is a similar view of a spirally grooved tool bod provided with diamonds; Fig. 3 is an en arged side elevation of the outer end of'the tool shown in Fig. 1;

Fig. 4 is a perspective view of theouter end of the same tool body prepared to receive diamonds;

Fig. 5 is an enlarged cross sectional view of a tool body showing the manner of locating and anchoring the diamonds, and

Fig. 6 is a longltudinal sectional view taken on the line VIV1 of Fi 5.

l-n carrying my method into e'l ect to provide a too this invention, I select a cylindrical metallic body 1 and provide the same with either longitudinal flutes 2 or piral grooves 3. As pointed out in the beginning, I may utilize an ordinary reamer body which has longitudinal flutes or I may utilize a bit or auger having spiral grooves. If such articles cannot be obtained in desired sizes, I may shape the body so that it will provide clearance for material to be removed by the tool.

Assuming that the reamer body 1 is used, I operate upon the outer end thereof to provide'alternating flute walls 4 with recesses 5 in which diamonds 6 may be placed with the diamonds braced by the alternating flute walls 14 and therefore extendin versely of alternating flutes 2. monds will block the ends of alternating flutes and besides projecting circumferentially or radially from the tool body said:

diamonds will project into those alternat ing flutes with which the recesses 5 com 'municate.

After placing the diamonds in the recesses 5, I place a sleeve-like retaining member 7 about the end of the tool body to retain the diamonds in position.

Next, I our molten brass 8 or other suitable materlal into the retaining member 7 to lodge about the diamonds 6 and anchor the same in the recesses 5 against the flute walls 14. This operation is ordinarily knownas brazing and the material 8 affordsa substantial diamond holding body 9 in the ends ofalternating flutes, as shown in Figs. 3 and 6. With the diamonds 6 firmly anchored I trans; he d1abody and drill in accordance with now remove the retaining member 7 and excess brazing mater1-al, as bestbrought out in Fi 3, so that desired cutting portions of the diamonds will be exposed to aflord side cutting edges and end cutting edges for the finished tool. With only certain of the flutes 2 blocked or closed at the outer ends thereof, the remaining flutes and portions.

thereof will provide clearance for such drilled or material as'is removed by the diamonds,thus permitting the tool to tions of the .i

a r I a: 1m ondB. Th in volve additional steps contributing towards the production ofa high grade diamond too],

empty 9. hole as fast as the same is boredMand consequently I do not care toconfine my the outer end of'the tool body with an axia' remss for an end diamond 11 which is used fortool centering tpurposes, like the point or screw on the on of an anger. At the same time the diamonds 6 are anchored in the tooibody, the diamond 11 may bealso anchored with sufiicient materialcut. away to expose a portion of thddiamond. Insome instancesit may be necessary to cut away end portions of the tool body, for instance, the extreme end wall and the outer end walls of the recesses 5, but suflicient stock is left to firmly brace the diamonds, during the use of the tool.

As shown in Fig. '2 thetool body may be provided with'recesses 12 between the spiral grooves thereof and in these recesses may be mounted diamonds 13 in a inanner similar to the mounting of the diamonds 6. The

diamond 11 maybe also located in'the end of the tool body, if no other provision has been made for centering or guidingthe-tool when in'use.

From the'foregoing it will be observed that I have-devised, as a new article of manufacture, a tool havin a centering diamond and diamonds dispose thereabout providing end and side cutting. ed es for the tool, and in producing this artic e of manufacture, substantially the following method is involved.

First, selecting a fluted or grooved body, or providing a tool body with flutes or grooves; second, cutting away the body at its ends to provide recesses;'th1rd, setting diamondsi in the recesses or cut away places of thetool bod fourth, securing the diamonds in lace by razing, and'fifth, trimming the ho y and the brazing material to; expose por- My invention further resides in providin invention to the method steps recited above or to the exact construction ente -mto the tool, other than defined by the appended claims. 7 k

WhatIclaiinis:

' V 1. A method-30f making drills consist' insiirst providing a reamer body; seco cutting away the reamer body at its ends; third, settin diamonds in the cut away places of sai reamer body; fourth, seouri the diamonds in place by brazing, and fifth, trimming the reamer body and its brazing material to expose portions of said diamonds. y

2. A method of maki drills involving the steps set forth in claim 1, and further characterized by usinga fluted reamer bod with the cut away laces communicating with the flutes of the dy so that walls of the flutes may brace the diamonds.

3. Amethod of converting a reamer body I into a diamond drill consisting in first cutti vi e transverse recesses; second,- plac' a retainer memberf- "",the recessed en of the reamer body; third, placin -diamonds in RRY W. OGOODL Witnesses:

mar C. Srmnnn, )1

an H. v

away walls of the reamer body to pro-' 

